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Hi, what is the recommended way of adding a handle for flow run interruption in Prefect 1.0 (similarly to `on_handle` argument of `Flow`)?

is this a test? :sweat_smile: afaik, there's no on_handle, do you mean on_failure?

if so, anytime you call a task or a subflow (without task runner), you can pass retiurn_state=True to get state and then you can act on it e.g. if state.name == "Failed" (or "Completed") and triggering downstream actions just with if/else

and for main flows, we are rolling out Automations to take action on various states of a flow run <https://prefect-community.slack.com/archives/CKNSX5WG3/p1670444624688239>

<@U02H1A95XDW> yes, I meant `on_failure` sry

```from prefect import flow, task
import random


@task
def on_failure_task():
    print("Taking action on failure here")


@task
def on_success_task():
    print("Taking action on success here")


@flow
def bad_subflow():
    if random.random() &gt; 0.5:
        raise ValueError("Non-deterministic error has occured.")


@flow(log_prints=True, name="Conditional subflows")
def main():
    state = bad_subflow(return_state=True)
    if state.name == "Failed":
        print("Subflow failed! Run on_failure_task")
        on_failure_task()
    else:
        print("Subflow succeeded! Run on_success_task")
        on_success_task()


if __name__ == "__main__":
    main()```


yes, I thought you made a typo there because the question suggested you know how to solve it in v1 but not how to migrate this to v2

generally, migration is highly recommended and encouraged

Overall in V1, there are flow level state handlers to solve the same problem, there are a couple of examples on Discourse for V1 if you check the tag state handlers